Dry-eye state may occur in a wide range of individuals, although it is more frequently seen in women, the elderly, and those with connective tissue disorders (e.g., rheumatoid arthritis, Sjögren's syndrome). Patients with dry eye commonly have complaints of ocular irritation or discomfort. As the name implies, dryness is the most frequently cited problem; patients may further report itching, burning, or a “sandy/gritty” foreign body sensation. Symptoms may be exacerbated by poor air quality, low humidity or extreme heat, and tend to be more prominent later in the day. Occasionally, patients report excess lacrimation, or epiphora, in association with the discomfort.
Uveitis, the inflammation of the uvea, is responsible for about 10% of the visual impairment in the United States. The uveal tract of the eye consists of the iris, ciliary body, and choroid. Inflammation of the overlying retina, called retinitis, or of the optic nerve, called optic neuritis, may occur with or without accompanying uveitis.
Uveitis is most commonly classified anatomically as anterior, intermediate, posterior, or diffuse. Anterior uveitis is localized primarily to the anterior segment of the eye and includes iritis and iridocyclitis. Intermediate uveitis, also called peripheral uveitis, is centered in the area immediately behind the iris and lens in the region of the ciliary body and pars plana, hence the alternate terms “cyclitis” and “pars planitis” are also used. Posterior uveitis signifies any of a number of forms of retinitis, choroiditis, or optic neuritis. Diffuse uveitis implies inflammation involving all parts of the eye, including anterior, intermediate, and posterior structures.
Phacoanaphylactic endophthalmitis is a human autoimmune disease. It is an inflammatory ocular condition secondary to rupture of the lens capsule, either traumatically or iatrogenically is also referred to as lens induced uveitis. Phacoanaphylaxis is a severe form of uveitis in which the lens is the causative antigen. The lens proteins are normally secluded by the lens capsule since before birth. When these proteins are released into the eye by injury or surgery or occasionally during cataract development, they can become intensely antigenic and incite an autoimmune response. If the response is moderate it is seen as a chronic uveitis. If it is very fast in progression the eye becomes severely inflamed in all segments. This latter response is named phacoanaphylaxis.
There is a continuing need to develop new and effective compounds to treat ocular diseases and disorders, such as dry eye, uveitis and phacoanaphylactic endophthalmitis.
Cyclosporins are a group of nonpolar cyclic oligopeptides with immunosuppressant, anti-inflammatory, and anti-parasitic properties. Cyclosporin A is a cyclosporin which is marketed in a topical ophthalmic emulsion formulation for the treatment of dry eye under the tradename Restasis. The insolubility of cyclosporins in water is an ongoing problem in the formulation of these compounds. In one aspect, the present invention seeks to provide cyclosporin derivatives having improved water solubility properties in comparison with cyclosporin A while maintaining useful properties for treating ocular diseases.